We’ve all heard of kidney stones,
but let’s get familiar.
These frequently painful little pebbles affect 1 in 10 women
and 1 in 5 men. And the statistics aren’t trending down. According
to the National Kidney Foundation, reported cases of kidney
stones have nearly tripled since the 1970s. This rise could be
attributed to high blood pressure, diabetes, and obesity.
By Nicole Jennings
So, What Exactly Are Kidney Stones?
Kidney stones, as the name implies, are hard objects that form in your kidneys when chemicals in your urine crystallize. They’re usually sharp and spiky, and they can range in size from a grain of salt to a golf ball. “The chemical composition of the urine and the anatomy of the urinary tract both play a part in determining the ultimate size of the stone that forms,” explains Dr. Joseph Veys, a urologist on the Hamilton Medical Center staff.
Regardless of the size, kidney stones are divided into four basic groups:
The most common type of kidney stone is usually composed of calcium and oxalate, a natural chemical found in most foods, but calcium and phosphate, another chemical found in foods, can also combine to form stones. Calcium stones are caused by insufficient calcium and dehydration.
More common in men than women, this type of kidney stone forms when your body doesn’t process certain chemicals, leaving your urine too acidic. While certain foods can increase your urine’s acidity level, these stones also tend to have a genetic component and run in families.
Struvite stones are often formed in women with urinary tract infections, and they tend to grow quickly. According to Dr. Veys, “Struvite tends to produce very large ‘staghorn’ stones that require more invasive techniques for removal.”
The rarest type of kidney stone, cystine stones are caused by a genetic disorder called “cystinuria.” Cystinuria causes a natural substance called “cystine” to leak into your urine, resulting in the formation of kidney stones.
There are many risk factors that can increase your chance of forming kidney stones. If you’ve had kidney stones before or have a family history of kidney stones, you’re at increased risk. Not being properly hydrated contributes to your risk too. Diets high in protein, sodium, or sugar intake also boost your odds, as does being overweight or having gastric bypass surgery. Your chances of forming stones are also increased if you frequently take medications such as diuretics or calcium-based antacids.
The Signs and Symptoms
Kidney stones don’t always cause noticeable signs or symptoms. Dr. Mark Currin, a urologist with CHI Memorial Urology Associates, explains, “In most cases, stones don’t cause symptoms. Stones themselves do not cause pain. The pain associated with stones occurs when they move into a position where they block the flow of urine out of the kidneys, which is known as an obstruction.”
That being said, when they do cause an obstruction, constant or fluctuating pain in the lower back or sides is a telltale sign. Dr. Veys adds, “The pain is often described as ‘worst I’ve ever had,’ and many women have said it’s worse than the pain of childbirth.”
Issues with urinating may also indicate a problem. You may experience a burning sensation; you may feel like you constantly have to urinate but you’re only able to go a little bit each time; or you may notice blood in your urine. Kidney stones are also likely to produce an unpleasant odor when urinating.
A fever and chills coupled with nausea, possible vomiting, and other kidney stone symptoms probably means your stone is causing an infection that can’t be resolved until after the stone has passed. This promotes it to a medical emergency, which means you should go to the emergency room immediately.
Kidney Stone Diagnosis and Treatment
Most of the time it can be pretty apparent when kidney stones are causing an obstruction, due to the severity and location of pain. After a physical exam and a health history, your doctor may order blood tests to check the levels of calcium and uric acid in your blood. Urine tests can confirm a kidney stone diagnosis by revealing too many stone-forming minerals or too few stone-preventing minerals. A doctor may also order imaging tests such as a CT scan, X-ray, or ultrasound.
Treatment depends on the size of the stone, where it’s located, and if it’s obstructing or
non-obstructing. Stones smaller than seven millimeters are often left to pass on their own. Drinking lots of water, accompanied by over-the-counter pain relievers to ease the discomfort, can help flush them out.
Larger or problematic stones can be treated with a procedure called extracorporeal shock wave lithotripsy (ESWL). “Shockwave lithotripsy is a procedure performed in the operating room where soundwaves focused on a stone are used to fragment the stone into sand, which passes easily and painlessly down the ureter,” explains Dr. Currin. “This is a non-invasive approach and is generally very well tolerated.”
Another treatment option is ureteroscopy. In this procedure, a doctor inserts an endoscope (a flexible tube with a lighted camera on the end) through the urethra. Through the camera, a laser may be passed and used to break up stones that are too large to remove.
More complex surgical procedures are options for cases where there is a significant amount of stone requiring treatment.
How to Prevent Kidney Stones
There are many precautions you can take to reduce your risk of kidney stones.
First and foremost, drink up! Water is best, but fluid in general is a necessity. It’s recommended that the average person drink eight to 12 cups of fluid a day, and chances are you’re not getting that much. Proper hydration helps dilute your urine and lessens kidney stone-causing waste buildup.
Second, reduce your salt intake. Urinary calcium, a main component of calcium oxalate stones, is increased by a high salt diet. You should also avoid red meat, organ meats, and shellfish when possible. These contain a high amount of purine, a natural chemical compound that contributes to the production of uric acid.
Third, eat more fruits and veggies. They’re good for you anyway, and since high blood pressure, diabetes, and obesity are suspected to increase your risk for kidney stones, any dietary and lifestyle changes you make to help reduce those can also reduce your risk of kidney stones.
Also, since calcium oxalate stones are the most common, lowering your intake of foods high in oxalate can help reduce your risk. These are foods like cocoa, chocolate, tea, rhubarb, beets, quinoa, kiwis, and soy products. However, if you pair your intake of oxalate-rich foods with foods that are high in calcium, it may be a better method than trying to cut oxalate from your diet altogether. As you digest, calcium and oxalate are more likely to bind together before they go through the kidneys, making it less probable that they’ll form stones.
Now that you know the ins and outs of kidney stones, just be mindful, listen to your body, and remember – all things in moderation. Be sure to consult your doctor with any questions or concerns!
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